1. Field of the Invention
The present invention relates to an ink jet recording head for recording a high-quality image at high speed with high reliability and an ink jet recording device equipped with the recording head, a manufacturing method of the recording head of the inkjet recording device.
2. Description of Related Art
For recording a high-quality image at high speed with high reliability by using a multi-nozzle on-demand ink jet recording head in which a lot of nozzles are integrated, it is important to reduce variations in the ink drop discharge speed or the ink drop weight among nozzles.
In an on-demand ink jet recording head according to push-type piezoelectric element system, a wall of an ink pressurizing chamber having nozzle apertures is formed of a diaphragm. By pushing the diaphragm with vertical vibrations of rod-like piezoelectric elements, the volume of the ink pressurizing chamber is decreased to discharge the ink drop. Conventionally, in the on-demand ink jet recording head according to push-type piezoelectric element system, in order to reduce variations in the ink drop discharge speed or weight among nozzles, the accuracy of components such as the piezoelectric elements and the ink pressurizing chamber is improved, or assembling accuracy of bonding of each part and the like is improved.
However, according to the above-mentioned method, there may cause disadvantages such as an increase in costs of parts and assembling time. On the contrary, Unexamined Patent Application Publication No. 2001-277525 discloses a method of reducing variations in the ink drop discharge speed or weight among nozzles by properly adjusting the polarization level of piezoelectric elements. According to this method, although it requires adjustment costs in a head manufacturing process, variations in the ink drop discharge speed and weight can be improved without adding any part or circuit.
However, according to the method disclosed in Unexamined Patent Publication No. 2001-277525, the ink discharge speed needs to be measured while varying a polarization level of each piezoelectric element in order to adjust the ink drop discharge speed of each nozzle of a recording head to a target speed. For this reason, since it takes time to measure the ink drop discharge speed and adjust the polarization level of the piezoelectric elements to a proper value, sufficient cost down and improvement in productivity cannot be achieved.